Replicating Cooktorr specular with Cycles vectors, almost there, but why vector is twisted?
Alright I found the issue, after reading the following observation about Cooktorr in blender dev:

https://developer.blender.org/T34564

I learned that Blender Internal Cooktorr was actually Blinn-Phong, so I reviewed the math of it and figured out which vector I had misplaced, I leave a picture with the solution, also the link to the math, for reference.

https://en.wikipedia.org/wiki/Blinn%E2%80%93Phong_shading_model